Forced air flow system for refrigerators

ABSTRACT

An improvement in the forced air flow system for refrigerators, comprising: at least two refrigeration environments ( 1, 2 ); and a refrigeration air impelling means ( 10 ) forcing the passage of an air flow from a refrigeration environment ( 1, 2 ) through a respective evaporator portion ( 4, 5 ) and comprising only one fan ( 11 ) associated with at least two suction chambers ( 12 ), which are each opened to a respective refrigeration environment ( 1, 2 ) and to at least two discharge chambers ( 13 ), which are each opened to an inlet side ( 6 ) of a respective evaporator portion ( 4, 5 ).

FIELD OF THE INVENTION

The present invention refers to an improvement in the forced air flowsystem for refrigerators having at least two refrigeration environments,particularly used in refrigerators and freezers in which the evaporatoris provided externally to the refrigeration environments and which haveindependent refrigeration air circuits communicating each refrigerationenvironments with the evaporator.

BACKGROUND OF THE INVENTION

In the refrigerators having two or more refrigeration environments, forexample a freezing compartment and a refrigerating compartment, and inwhich the evaporator is provided externally to said refrigerationenvironments, the refrigeration of the latter is obtained by forcedcirculation of air flows through the evaporator, said forced circulationbeing made by an impelling means, usually a fan provided adjacent to anair passage between the freezing and refrigerating compartments.

In some known constructions, the air flow of the different refrigerationenvironments of the refrigerator is mixed in a return duct of arefrigeration air circuit, which duct is common to said compartments,said air flow being then conducted to the environment of the evaporatorand cooled therein, before re-conducted to these compartments. Since theconditions of temperature and air humidity in these environments aredistinct, the mixture of air flows to promote the refrigeration of theseenvironments, by passing through the evaporator, results in energeticlosses.

In other known constructions, the refrigerator has, for eachrefrigeration environment, a respective refrigeration air circuit whichcommunicates the air flow of the respective environment with theenvironment of the evaporator. In these constructions, the air flow ofeach refrigeration environment is forced to pass through the evaporator,through the respective air circuit, which is provided with a respectivefan.

In these constructions, in order that the air flows do not mix, even inthe region of the evaporator, it should be provided, for eachrefrigeration circuit, respective components, including for example, theevaporator, which increases the cost of the product. Besides increasingthe cost of the product, a higher number of components makes morecomplex the assembly of this product and leaves this product moresusceptible to failures, requiring more frequent maintenance service.

As a function of the limitations of the available space for installingthe components, such constructions require smaller mechanicalcomponents, which usually have low efficiency, causing losses. Moreover,a higher number of components allows the occurrence of noises.

DISCLOSURE OF THE INVENTION

Thus, it is an objective of the present invention to provide animprovement in the forced air flow system for refrigerators, whichallows a substantial segregation of the forced air flows between therefrigeration environments, with a simple construction, of easy assemblyand maintenance, which uses few components, but with a low cost. Theseand other objectives are achieved by an improvement in the forced airflow system for refrigerators, comprising: at least two refrigerationenvironments; and refrigeration air impelling means, having a suctionside and a discharge side and forcing the passage of an air flow from arefrigeration environment through a respective evaporator portion, eachevaporator portion having an outlet side opened to a respectiverefrigeration environment, the refrigeration air impelling meanscomprising only one fan associated with at least two suction chambers,which are each opened to a respective refrigeration environment and toat least two discharge chambers, which are each opened to an inlet sideof a respective evaporator portion.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described below, with reference to the attacheddrawings, in which:

FIG. 1 illustrates, schematically, a front view of a cabinet, withoutthe door, of a refrigerator, in relation to which the present inventionwill be described;

FIG. 2 illustrates, schematically and in a lateral longitudinalsectional view, according to line II—II of FIG. 1, showing the impellingmeans of the present invention and part of a refrigeration circuit forthe freezing compartment of the refrigerator;

FIG. 3 illustrates, schematically and in a lateral longitudinalsectional view, according to line III—III of FIG. 1, showing theimpelling means of the present invention and part of a refrigerationcircuit for the freezing compartment of the refrigerator;

FIG. 4 illustrates, schematically and in a perspective view, the part ofthe air flow system of the present invention, showing the evaporator,the refrigeration ducts and the impelling means; and

FIG. 5 illustrates, schematically and in a perspective view, aconstruction for the impelling means of the present invention.

BEST MODE OF CARRYING OUT THE PRESENT INVENTION

The present invention will be described in relation to a refrigerator orfreezer, such as that disclosed in the copending patent application ofthe same applicant and filed on Jun. 22, 1999, with the title “AnAutomatic Defrost System for a Refrigerating Device” and which includes,inside a cabinet, at least two refrigeration environments, for exampledefined by at least one of the freezing compartment 1 and therefrigerating compartment 2, which are in selective fluid communicationwith an evaporator 3 (for example provided in an environment externaland adjacent to a rear wall of the freezing compartment 1) and whosetemperatures are maintained within a temperature interval, which ispreviously defined as the ideal operation interval, as a function of theoperation of a non-illustrated compressor.

The evaporator 3 comprises evaporator portions 4 and 5, each having arespective inlet side 6 operatively connected to and in selective fluidcommunication with a refrigeration air impelling means 10 of a forcedair flow system, to be described below, and an outlet side, in fluidcommunication with a respective refrigeration environment 1, 2. Eachinlet side defines an air chamber associated with a respective air ductin the respective evaporator portion 4, 5 and which is defined betweenat least two vertical fins 7 adjacent to each other and belonging to thecorresponding evaporator portion 4, 5.

In the illustrated construction, the evaporator 3 is of the tube-fintype, with vertical fins 7 arranged parallel to each other definingducts for the passage of the air flow to be directed to one of therefrigeration environments 1, 2. In this construction, the evaporator 3comprises a vertical plate 8, provided parallel between the verticalfins of said evaporator 3, separating its two portions, said verticalplate 8 being, for example, defined by a fin of the evaporator 3 havingat least one end portion 9 projecting from a plane containing end edgesof the same side of the other vertical fins 7 of the evaporator 3.

The refrigeration air impelling means 10 has a suction side and adischarge side and forces the passage of an air flow of eachrefrigeration environment 1, 2 through a respective evaporator portion4, 5, each of the latter having a respective outlet side opened to arespective refrigeration environment 1, 2.

The refrigeration air impelling means 10 of the present inventioncomprises, for example, a single fan 11, associated with at least twosuction chambers 12, each being opened to a respective refrigerationenvironment 1, 2 and to at least two discharge chambers 13, each of thelatter being opened to the inlet side 6 of a respective evaporatorportion 4, 5. According to the present invention, at least one of thesuction 12 and discharge chambers 13 of the refrigeration air impellingmeans 10 is opened to a nozzle of a respective refrigeration duct 20,which conducts the respective refrigeration air flow to one of the partsdefined by the refrigeration environments 1, 2 and inlet side 6 of theevaporator portions 4, 5. In the illustrated construction, therefrigeration air impelling means 10 has two suction chambers 12 and twodischarge chambers 13, each suction chamber 12 being axially andsubstantially aligned with a respective discharge chamber 13 and openedto a nozzle of a respective refrigeration duct 20.

According to the illustrated embodiment, the refrigeration air flowsystem of the present invention has: two refrigeration ducts 20, eachinterconnecting a respective refrigeration environment 1, 2 to a suctionchamber 12 of the air flow impelling means 10, each refrigeration duct20 having an inlet nozzle 21 opened to the respective refrigerationenvironment 1, 2, and an outlet nozzle 22 opened to the respectivesuction chamber 12; and two refrigeration ducts 20, each interconnectinga discharge chamber 13 of the air flow impelling means 10 to a nozzle onthe inlet side 6 of a respective evaporator portion 4, 5, eachrefrigeration duct 20 having an inlet nozzle 21 opened to a respectivedischarge chamber 13 of the air flow impelling means 10 and an outletnozzle 22 opened to the nozzle of the inlet side 6 of a respectiveevaporator portion 4, 5.

The refrigeration ducts 20 interconnecting the air flow impelling means10 to the evaporator 3 have their respective inlet nozzles 21 verticallyaligned to each other and their outlet nozzles 22 horizontally andvertically spaced from each other, each one opened to a nozzle of avalve means 30 containing an obturator for each said outlet nozzle 22and constructed, for example, such as that described in the copendingpatent application, of the same applicant, filed on Jun. 22, 1999, underthe title “An Automatic Defrost System for a Refrigerating Device” (FIG.4).

According to the illustrations in FIGS. 2 and 3, the inlet nozzles 21 ofthe refrigeration ducts 20 interconnecting each refrigerationenvironment 1, 2 to the air flow impelling means 10, have a substantialvertical alignment, said inlet nozzles 21 converging when they arepositioned in the direction towards the respective suction chamber 12 ofsaid air flow impelling means 10.

The air flow system of the present invention further comprises a supportstructure 14 carrying the fan 11 and defining part of the refrigerationducts 20 which interconnect the discharge side of the fan to the inletside of the evaporator portions 4, 5.

The support structure 14 has a plate portion 15 positioned substantiallycoplanar to the rotation axis of the fan 11 and defines a wall portion,which is common to the refrigeration ducts 20 interconnecting thedischarge side of the fan 11 with the inlet side of the evaporatorportions 4, 5.

The plate portion 15 defines, for each air flow, a respective deflector16, maintaining, in a substantially axial and segregated way, each saidair flow through the fan 11.

In the construction illustrated in FIG. 5, the support structure 14further has an external ring 17, which is circumferentially external tothe maximum circumference defined by the external edges of the blades ofthe fan 11 and which circumferentially locks the support structure 40 tothe body of the refrigerator cabinet.

The plate portion 15 extends to both suction and discharge sides of thefan 11 and, in its portion adjacent to the suction side, further carriesa drive unit 30 for driving the fan 11.

With the refrigeration air flow system of the present invention, therefrigeration air of each environment flows between the latter and theevaporator in a substantially segregated way, with a maximum of about 5%mixture.

Thus, by varying the air flow speed and refrigeration area parameters ofthe respective evaporator portion, there is obtained a refrigeration ofthe respective refrigeration environment with more adequate temperatureand humidity conditions for said environment, such as for example, arefrigeration compartment with a temperature not so cold as that of thefreezing compartment and with higher humidity, which is necessary forpreventing the food stored inside the freezing compartment from beingcold burned.

What is claimed is:
 1. An improvement in the forced air flow system forrefrigerators, comprising: at least two refrigeration environments (1,2); and a refrigeration air impelling means (10), having a suction sideand a discharge side and forcing the passage of an air flow from arefrigeration environment (1, 2) through a respective evaporator portion(4, 5), each evaporator portion (4, 5) having an outlet side opened to arespective refrigeration environment (1, 2), characterized in that therefrigeration air impelling means (10) comprises only one fan (11)associated with at least two suction chambers (12), which are eachopened to a respective refrigeration environment (1, 2) and to at leasttwo discharge chambers (13), which are each opened to an inlet side (6)of a respective evaporator portion (4, 5).
 2. Improvement, as in claim1, characterized in that at least one of the suction and dischargechambers (12, 13) of the fan (11) is opened to nozzles of the respectiverefrigeration ducts (20) conducting to one of the parts defined by therefrigeration environments (1, 2) and the inlet side (6) of theevaporator portions (4, 5).
 3. Improvement, as in claim 2, characterizedin that each suction chamber (12) is axially and substantially alignedwith a respective discharge chamber (13).
 4. Improvement, as in claim 3,characterized in that the refrigeration ducts (20) interconnecting thefan (11) with the inlet side of the evaporator portions (4, 5) haverespective inlet nozzles (21) which are vertically aligned to each otherand outlet nozzles (22) which are horizontally and vertically spacedfrom each other.
 5. Improvement, as in claim 4, characterized in thatthe evaporator portions (4, 5) are in the form of vertical ducts definedby at least two vertical fins (7) which are adjacent to each other andof a single evaporator (3).
 6. Improvement, as in claim 5, characterizedin that the evaporator (3) comprises a vertical plate (8) parallelyprovided between the vertical fins (7) of said evaporator (3),separating the two portions thereof.
 7. Improvement, as in claim 6,characterized in that the vertical plate (8) is defined by a verticalfin (7) of the evaporator (3) having at least one end portion (9)projecting from a plane containing end edges at the same side of theother vertical fins (7) of the evaporator (3).
 8. Improvement, as inclaim 7, characterized in that it comprises a support structure (14)carrying the fan (11) and defining part of the refrigeration ducts (20)which interconnect the discharge side of the fan (11) to the inlet side(6) of the evaporator portions (4, 5).
 9. Improvement, as in claim 8,characterized in that the support structure (14) has a plate portion(15) positioned substantially coplanar with the rotation axis of the fan(11) and defines a wall portion common to both refrigeration ducts (20)interconnecting the discharge side of the fan (11) with the inlet side(6) of the evaporator portions (4, 5).
 10. Improvement, as in claim 9,characterized in that the plate portion (15) defines, for each air flow,a respective deflector (16), maintaining, in a substantial axial andsegregated way, each air flow through the fan (11).
 11. Improvement, asin claim 10, characterized in that each refrigeration duct (20)connecting the discharge side of the fan (11) with the inlet side (6) ofthe evaporator portions (4, 5) contains obturating means for selectivelyblocking the respective segregated air flow.